Broadband Digital T / R Module Key

With the development of digital technique, the function that can only be implemented by analog circuits or analog technique , now can be implemented by digital circuits or digital technique. The procedure of phased shifting in phased array radar will become a digital procedure eventually. Digital T/R module use DDS(DDFS and DDWS) technique to implement amplitude and phase weighting, it can achive transmitting beamforming in IF or lower frequency by using digital method whitch realizes phase control and amplitude weighting. this dissertation discuss the key technology of wide band digital T/R module , including: Architecture of the wide band digital T/R module; Wide band signal generating technology based on DDWS; Using fiber technology to transmit data between radar center and T/R moudle.After studying the digtal T/R module technology over the world , this dissertation present a scheme of L band(1300MHz) wide band(B=100MHz) digital T/R module , and design a test board to verify transmitting technology of wide band digital T/R module, it works at L band .It use Gigabit fiber components to transmit data between radar center and T/R module, use DDWS and quadrature modulate technology to generate wide band radar transmitting signal, all control signal is generated by FPGA.Chapter 1 briefly introduce the background and the development of digital T/R module, later introduce the main work of this dissertation. In chapter 2, First give the theory of phased array radar. Second introduce the analog T/R module and digital T/R module.Third discusses some key technology of wide band digital T/R module, including DDWS technology and quadrature modulate technology. At last present a scheme of L bandwide banddigital T/R module. Chapter 3 introduce the circuit design of wide band digital T/R module transmission channel. Chapter 4 introduce the FPGA software design of wide band digital T/R module transmission channel. Chapter 5 introduce the design of the fiber data transmission card bassed on PCI bus, and give the debug result of wide band digital T/R module transmission channel.The main work in this dissertation is as follows:1. Have presented a scheme of L band wide band digital T/R module.